Готові списки джерел за темами / Front Face Flash Method

Добірка наукової літератури з теми "Front Face Flash Method"

Автор: Grafiati

Опубліковано: 8 травня 2022

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Статті в журналах з теми "Front Face Flash Method":

Forero-Sandoval, I. Y., N. W. Pech-May, and J. J. Alvarado-Gil. "Measurement of the thermal transport properties of liquids using the front-face flash method." Infrared Physics & Technology 93 (September 2018): 9–15. http://dx.doi.org/10.1016/j.infrared.2018.07.009.

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Hay, B., J. R. Filtz, J. Hameury, G. Davée, L. Rongione, and O. Enouf. "Thermal-Diffusivity Measurement of Ceramic Coatings at High Temperature using “Front-Face” and “Rear-Face” Laser Flash Methods." International Journal of Thermophysics 30, no. 4 (January 31, 2009): 1270–82. http://dx.doi.org/10.1007/s10765-009-0560-z.

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Vadathya, Anil Kumar, Salma Musaad, Alicia Beltran, Oriana Perez, Leo Meister, Tom Baranowski, Sheryl O. Hughes, et al. "An Objective System for Quantitative Assessment of Television Viewing Among Children (Family Level Assessment of Screen Use in the Home-Television): System Development Study." JMIR Pediatrics and Parenting 5, no. 1 (March 24, 2022): e33569. http://dx.doi.org/10.2196/33569.

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Background Television viewing among children is associated with developmental and health outcomes, yet measurement techniques for television viewing are prone to errors, biases, or both. Objective This study aims to develop a system to objectively and passively measure children’s television viewing time. Methods The Family Level Assessment of Screen Use in the Home-Television (FLASH-TV) system includes three sequential algorithms applied to video data collected in front of a television screen: face detection, face verification, and gaze estimation. A total of 21 families of diverse race and ethnicity were enrolled in 1 of 4 design studies to train the algorithms and provide proof of concept testing for the integrated FLASH-TV system. Video data were collected from each family in a laboratory mimicking a living room or in the child’s home. Staff coded the video data for the target child as the gold standard. The accuracy, sensitivity, specificity, positive predictive value, and negative predictive value were calculated for each algorithm, as compared with the gold standard. Prevalence and biased adjusted κ scores and an intraclass correlation using a generalized linear mixed model compared FLASH-TV’s estimation of television viewing duration to the gold standard. Results FLASH-TV demonstrated high sensitivity for detecting faces (95.5%-97.9%) and performed well on face verification when the child’s gaze was on the television. Each of the metrics for estimating the child’s gaze on the screen was moderate to good (range: 55.1% negative predictive value to 91.2% specificity). When combining the 3 sequential steps, FLASH-TV estimation of the child’s screen viewing was overall good, with an intraclass correlation for an overall time watching television of 0.725 across conditions. Conclusions FLASH-TV offers a critical step forward in improving the assessment of children’s television viewing.

Pech-May, Nelson W., Caridad Vales-Pinzón, Alejandro Vega-Flick, Ángel Cifuentes, Alberto Oleaga, Agustín Salazar, and Juan J. Alvarado-Gil. "Study of the thermal properties of polyester composites loaded with oriented carbon nanofibers using the front-face flash method." Polymer Testing 50 (April 2016): 255–61. http://dx.doi.org/10.1016/j.polymertesting.2015.12.011.

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Groz, Marie-Marthe, Mohamed Bensalem, Alain Sommier, Emmanuelle Abisset-Chavanne, Stéphane Chevalier, Arsenii Chulkov, Jean-Luc Battaglia, Jean-Christophe Batsale, and Christophe Pradere. "Estimation of Thermal Resistance Field in Layered Materials by Analytical Asymptotic Method." Applied Sciences 10, no. 7 (March 30, 2020): 2351. http://dx.doi.org/10.3390/app10072351.

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In this paper, the problem of the quantitative characterization of thermal resistance fields in a multilayer sample is addressed by using the classical front face flash method as the thermal excitation and infrared thermography (IRT) as the monitoring sensor. In this challenging problem, the complete inverse processing of a multilayer analytical model is difficult due to the lack of sensitivity of some parameters (layer thickness, depth of thermal resistance, etc.) and the expansive computational iterative processing. For these reasons, the proposed strategy is to use a simple multilayer problem where only one resistive layer is estimated. Moreover, to simplify the inverse processing often based on iterative methods, an asymptotic development method is proposed here. Regarding the thermal signal reconstruction (TSR) methods, the drawback of these methods is the inability to be quantitative. To overcome this problem, the method incorporates a calibration process originating from the complete analytical quadrupole solution to the thermal problem. This analytical knowledge allows self-calibration of the asymptotic method. From this calibration, the quantitative thermal resistance field of a sample can be retrieved with a reasonable accuracy lower than 5%.

Khaldirian, M. F., A. P. Rahardjo, D. Luknanto, and R. D. R. Sondi. "An Alternative Algorithm for Simulating Flash Flood." IOP Conference Series: Earth and Environmental Science 930, no. 1 (December 1, 2021): 012076. http://dx.doi.org/10.1088/1755-1315/930/1/012076.

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Abstract Most of the approaches in numerical modeling techniques are based on the Eulerian coordinate system. This approach faces difficulty in simulating flash flood front propagation. This paper shows an alternative method that implements a numerical modeling technique based on the Lagrangian coordinate system to simulate the water of debris flow. As for the interaction with the riverbed, the simulation uses an Eulerian coordinate system. The method uses the conservative and momentum equations of water and sediment mixture in the Lagrangian form. Source terms represent deposition and erosion. The riverbed in the Eulerian coordinate system interacts with the flow of the mixture. At every step, the algorithm evaluates the relative position of moving nodes of the flow part to the fixed nodes of the riverbed. Computation of advancing velocity and depth uses the riverbed elevation, slope data, and the bed elevation change computation uses the erosion or deposition data of the flow on the moving nodes. Spatial discretization is implementing the Galerkin method. Furthermore, temporal discretization is implementing the forward difference scheme. Test runs show that the algorithm can simulate downward, upward, and reflected backward 1-D flow cases. Two-D model tests and comparisons with SIMLAR software show that the algorithm works in simulating debris flow.

Duquesne, Loys, Christophe Lorrette, Christophe Pradère, Gérard Louis Vignoles, and Jean-Christophe Batsale. "A flash characterisation method for thin cylindrical multilayered composites based on the combined front and rear faces thermograms." Quantitative InfraRed Thermography Journal 13, no. 2 (June 2, 2016): 182–94. http://dx.doi.org/10.1080/17686733.2016.1165958.

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Pech-May, Nelson Wilbur, Arantza Mendioroz, and Agustín Salazar. "Generalizing the flash technique in the front-face configuration to measure the thermal diffusivity of semitransparent solids." Review of Scientific Instruments 85, no. 10 (October 2014): 104902. http://dx.doi.org/10.1063/1.4897619.

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Peng, Wanyue, and Richard B. Wilson. "Thermal model for time-domain thermoreflectance experiments in a laser-flash geometry." Journal of Applied Physics 131, no. 13 (April 7, 2022): 134301. http://dx.doi.org/10.1063/5.0082549.

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Time-domain thermoreflectance (TDTR) is a well-established pump–probe method for measuring thermal conductivity and interface conductance of multilayers. Interpreting signals in a TDTR experiment requires a thermal model. In standard front/front TDTR experiments, both pump and probe beams typically irradiate the surface of a multilayer. As a result, existing thermal models for interpreting thermoreflectance experiments assume that the pump and probe beams both interact with the surface layer. Here, we present a frequency-domain solution to the heat-diffusion equation of a multilayer in response to nonhomogeneous laser heating. This model allows analysis of experiments where the pump and probe beams irradiate opposite sides of a multilayer. We call such a geometry a front/back experiment to differentiate such experiments from standard TDTR experiments. As an example, we consider a 60nm amorphous Si film. We consider how signals differ in a front/front vs front/back geometry and compare thermal model predictions to experimental data.

Pech-May, Nelson Wilbur, Ángel Cifuentes, Arantza Mendioroz, Alberto Oleaga, and Agustín Salazar. "Simultaneous measurement of thermal diffusivity and effusivity of solids using the flash technique in the front-face configuration." Measurement Science and Technology 26, no. 8 (July 16, 2015): 085017. http://dx.doi.org/10.1088/0957-0233/26/8/085017.

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Дисертації з теми "Front Face Flash Method":

Faugeroux, Olivier. "Caractérisation thermophysique de revêtements de protection thermomécanique par méthode photothermique impulsionnelle." Perpignan, 2001. http://www.theses.fr/2001PERP0459.

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Ayvazyan, Vigen. "Etude de champs de température séparables avec une double décomposition en valeurs singulières : quelques applications à la caractérisation des propriétés thermophysiques des matérieux et au contrôle non destructif." Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14671/document.

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La thermographie infrarouge est une méthode largement employée pour la caractérisation des propriétés thermophysiques des matériaux. L’avènement des diodes laser pratiques, peu onéreuses et aux multiples caractéristiques, étendent les possibilités métrologiques des caméras infrarouges et mettent à disposition un ensemble de nouveaux outils puissants pour la caractérisation thermique et le contrôle non desturctif. Cependant, un lot de nouvelles difficultés doit être surmonté, comme le traitement d’une grande quantité de données bruitées et la faible sensibilité de ces données aux paramètres recherchés. Cela oblige de revisiter les méthodes de traitement du signal existantes, d’adopter de nouveaux outils mathématiques sophistiqués pour la compression de données et le traitement d’informations pertinentes. Les nouvelles stratégies consistent à utiliser des transformations orthogonales du signal comme outils de compression préalable de données, de réduction et maîtrise du bruit de mesure. L’analyse de sensibilité, basée sur l’étude locale des corrélations entre les dérivées partielles du signal expérimental, complète ces nouvelles approches. L'analogie avec la théorie dans l'espace de Fourier a permis d'apporter de nouveaux éléments de réponse pour mieux cerner la «physique» des approches modales.La réponse au point source impulsionnel a été revisitée de manière numérique et expérimentale. En utilisant la séparabilité des champs de température nous avons proposé une nouvelle méthode d'inversion basée sur une double décomposition en valeurs singulières du signal expérimental. Cette méthode par rapport aux précédentes, permet de tenir compte de la diffusion bi ou tridimensionnelle et offre ainsi une meilleure exploitation du contenu spatial des images infrarouges. Des exemples numériques et expérimentaux nous ont permis de valider dans une première approche cette nouvelle méthode d'estimation pour la caractérisation de diffusivités thermiques longitudinales. Des applications dans le domaine du contrôle non destructif des matériaux sont également proposées. Une ancienne problématique qui consiste à retrouver les champs de température initiaux à partir de données bruitées a été abordée sous un nouveau jour. La nécessité de connaitre les diffusivités thermiques du matériau orthotrope et la prise en compte des transferts souvent tridimensionnels sont complexes à gérer. L'application de la double décomposition en valeurs singulières a permis d'obtenir des résultats intéressants compte tenu de la simplicité de la méthode. En effet, les méthodes modales sont basées sur des approches statistiques de traitement d'une grande quantité de données, censément plus robustes quant au bruit de mesure, comme cela a pu être observé
Infrared thermography is a widely used method for characterization of thermophysical properties of materials. The advent of the laser diodes, which are handy, inexpensive, with a broad spectrum of characteristics, extend metrological possibilities of infrared cameras and provide a combination of new powerful tools for thermal characterization and non destructive evaluation. However, this new dynamic has also brought numerous difficulties that must be overcome, such as high volume noisy data processing and low sensitivity to estimated parameters of such data. This requires revisiting the existing methods of signal processing, adopting new sophisticated mathematical tools for data compression and processing of relevant information.New strategies consist in using orthogonal transforms of the signal as a prior data compression tools, which allow noise reduction and control over it. Correlation analysis, based on the local cerrelation study between partial derivatives of the experimental signal, completes these new strategies. A theoretical analogy in Fourier space has been performed in order to better understand the «physical» meaning of modal approaches.The response to the instantaneous point source of heat, has been revisited both numerically and experimentally. By using separable temperature fields, a new inversion technique based on a double singular value decomposition of experimental signal has been introduced. In comparison with previous methods, it takes into account two or three-dimensional heat diffusion and therefore offers a better exploitation of the spatial content of infrared images. Numerical and experimental examples have allowed us to validate in the first approach our new estimation method of longitudinal thermal diffusivities. Non destructive testing applications based on the new technique have also been introduced.An old issue, which consists in determining the initial temperature field from noisy data, has been approached in a new light. The necessity to know the thermal diffusivities of an orthotropic medium and the need to take into account often three-dimensional heat transfer, are complicated issues. The implementation of the double singular value decomposition allowed us to achieve interesting results according to its ease of use. Indeed, modal approaches are statistical methods based on high volume data processing, supposedly robust as to the measurement noise

Частини книг з теми "Front Face Flash Method":

Tuan, Nguyen Anh. "The Application of Finite Element Method to Analyze Passive Failure and Deformation Mechanisms of Soil in Front of Tunnel Face." In Proceedings of Fifth International Congress on Information and Communication Technology, 155–63. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-5859-7_15.

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Fox, Raymond. "Case/Critical Incident." In The Use of Self. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780190616144.003.0018.

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The core of teaching is the serious obligation to ‘‘touch’’ students. Providing more than the mere rudiments of knowledge is essential. Involvement is critical. Case study and critical incident examination are means to that end. To become competent practitioners, students need to develop the ability to incorporate knowledge, and, more important, to apply it in their practice. At the end of the day, student/practitioners will have clients in front of them for whom they need to decide what action to take. Prerequisite know-how and skill involve understanding clients’ motivation, background, thinking, behavior, affects, and concerns, combined with external forces affecting their lives. It includes the disciplined ability to select strategies and techniques appropriate to clients’ conditions and circumstances. Lead by example. Students pick up what they observe you do. Just as you endeavor to provide a rationale for what you do with students, so students gather how to provide a rationale for what they do with clients. Disciplined practice demands that practitioners continually monitor and evaluate their efforts to assure consonance with professional values and ethics. The case method encompasses all of these facets. Before entering the workforce to face flesh-and-bone clients, the case method provides students with an impressionistic chunk of reality. They become stakeholders in credible dilemmas. While certainly not perfect recreations of true situations, case studies, compared to other methods, bring students closer to what they need to keep in mind when dealing with real people. The case can be the lesson. As mentioned throughout this book, a parallel exists between what happens in the classroom and what happens in clinical practice. Cases—particularly in the manner in which you draw upon them interactively—exemplifies for students how they might deal with similar client situations. To use it to its best advantage, consider that the very manner you respond and interact with students as you ponder cases demonstrates for them ways to respond and interact with clients. The case method is predicated on three key notions of instruction.

Yigit, Tuncay, Arif Koyun, Asim Sinan Yuksel, Ibrahim Arda Cankaya, and Utku Kose. "An Example Application of an Artificial Intelligence-Supported Blended Learning Education Program in Computer Engineering." In Artificial Intelligence Applications in Distance Education, 192–210. IGI Global, 2015. http://dx.doi.org/10.4018/978-1-4666-6276-6.ch012.

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Blended Learning is a learning model that is enriched with traditional learning methods and online education materials. Integration of face-to-face and online learning with blending learning can enhance the learning experience and optimize seat time. In this chapter, the authors present the teaching of an Algorithm and Programming course in Computer Engineering Education via an artificial intelligence-supported blended learning approach. Since 2011, Computer Engineering education in Suleyman Demirel University Computer Engineering Department is taught with a blended learning method. Blended learning is achieved through a Learning Management System (LMS) by using distance education technology. The LMS is comprised of course materials supported with flash animations, student records, user roles, and evaluation systems such as surveys and quizzes that meet SCORM standards. In this chapter, the related education process has been supported with an intelligent program, which is based on teaching C programming language. In this way, it has been aimed to improve educational processes within the related course and the education approach in the department. The blended learning approach has been evaluated by the authors, and the obtained results show that the introduced artificial intelligence-supported blended learning education program enables both teachers and students to experience better educational processes.

Yigit, Tuncay, Arif Koyun, Asim Sinan Yuksel, Ibrahim Arda Cankaya, and Utku Kose. "An Example Application of an Artificial Intelligence-Supported Blended Learning Education Program in Computer Engineering." In Intelligent Systems, 1304–23. IGI Global, 2018. http://dx.doi.org/10.4018/978-1-5225-5643-5.ch056.

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Anitha R, Rakesh Gupta G, Manoj V, and Bhargav M. "Person Identification Using Face and Speech Recognition for Visually Challenged with Mask Detection." In Advances in Parallel Computing Technologies and Applications. IOS Press, 2021. http://dx.doi.org/10.3233/apc210125.

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A system and method for facilitating a visually impaired person for identifying a person. The method includes the step of storing a plurality of instructions for facilitating the visually impaired person identify the person in front of them by their face and/or voice characteristics by updating our project with Mask Detection using OpenCv and keras. It includes the step of receiving voice signals from the person present in surrounding of the visually impaired person and includes the step of capturing the pictures of a particular person and their surroundings of the visually impaired person and storing the processed data into the database or any storage devices. The data will be processed to AWS server or any local storage for processing and determining the person with the help of the database we already have. After processing and identifying the person with the help of face and voice recognition modules the name is sent to the visually impaired user’s phone in the form of a text message which will be read aloud by his phone’s virtual assistant.

Pant, Vibhanshu, Deepak Sharma, Annapurani. K, and R. Sundar. "Online Attendance Marking System Using Facial Recognition and Intranet Connectivity." In Recent Trends in Intensive Computing. IOS Press, 2021. http://dx.doi.org/10.3233/apc210247.

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Keeping up the attendance record with everyday exercises is a difficult task. The conventional method of marking staff attendance is by tapping their ID card and then using fingerprint scanner. But due to COVID-19 pandemic the attendance system of using fingerprint scanner is stalled and currently not in use. The following system depends on face recognition and intranet connectivity to keep up attendance record of facilities and staff. The paper discusses the attendance marking system that is passive (no direct contact with the scanner or sensor) and restricting the users within certain network. The main goal of this system is divided in two steps, in initial step face is snare from the front camera of the smart phone and it is then recognized in the picture and in the second step these distinguished appearances and features are contrasted with stored information in data set for confirmation.

Тези доповідей конференцій з теми "Front Face Flash Method":

Duquesne, L., C. Lorrette, C. Pradere, G. L. Vignoles, and J.-C. Batsale. "Simultaneous front and rear faces flash characterization method for thin cylindrical multilayered composites." In 2014 Quantitative InfraRed Thermography. QIRT Council, 2014. http://dx.doi.org/10.21611/qirt.2014.162.

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Balageas, D. "Thickness or diffusivity measurements from front-face flash experiments using the TSR (thermographic signal reconstruction) approach." In 2010 Quantitative InfraRed Thermography. QIRT Council, 2010. http://dx.doi.org/10.21611/qirt.2010.011.

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DEWITT, DAVID, and ROGER RONDEAU. "Evaluation of a method for measuring front-face surface temperaturesand spectral emissivities during irradiation." In 22nd Thermophysics Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 1987. http://dx.doi.org/10.2514/6.1987-1565.

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Lin, Bochuan, Shen Zhu, Heng Ban, Chao Li, Rosalia N. Scripa, Ching-Hua Su, and Sandor L. Lehoczky. "Modified Laser Flash Method for Thermal Property Measurements and the Influence of Heat Convection." In ASME 2003 International Mechanical Engineering Congress and Exposition. ASMEDC, 2003. http://dx.doi.org/10.1115/imece2003-41734.

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This study examined the effect of natural convection in the modified laser flash method for the measurement of thermo physical properties of semiconductor melts. Common laser flash method uses a laser pulse to heat the front surface of a thin circular sample and measures the temperature transient of the rear surface. Thermal diffusivity is calculated based on the analysis of the transient heat conduction process. For semiconductor melts, the sample is contained in a specially designed quartz cell with optical windows. When the laser pulse heats the melt front surface, the resulting natural convection can introduce errors in the calculation of thermal diffusivity based on the heat conduction model. The effect of natural convection was evaluated by Computational Fluid Dynamics (CFD) simulations in this study. The results indicated that natural convection can decrease the time needed for the rear surface to reach its peak temperature, and can also decrease the peak temperature slightly. Based on our experimental data for Tellurium, the calculation using only heat conduction model resulted in a thermal diffusivity about 3% greater than that using the heat transfer model with natural convection.

Naveira, Carolina P., Renato M. Cotta, Mohammed Lachi, and Jacques Padet. "Transient Conjugated Conduction: External Convection With Front Face Imposed Wall Heat Flux." In ASME 2007 International Mechanical Engineering Congress and Exposition. ASMEDC, 2007. http://dx.doi.org/10.1115/imece2007-41417.

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This work presents hybrid numerical-analytical solutions for transient laminar forced convection over flat plates of non-negligible thickness, subjected to arbitrary time variations of applied wall heat flux at the interface fluid-solid wall. This conjugated conduction-convection problem is first simplified through the employment of the Coupled Integral Equations Approach (CIEA) to reformulate the heat conduction problem on the plate by averaging the related energy equation in the transversal direction. As a result, a partial differential formulation for the average wall temperature is obtained, while a third kind boundary condition is achieved for the fluid in the heat balance at the solid-fluid interface. From the available velocity distributions, the solution method is then proposed for the coupled partial differential equations, based on the Generalized Integral Transform Technique (GITT) under its partial transformation mode, combined with the method of lines implemented in the Mathematica 5.2 routine NDSolve.

Lyras, Konstantinos, Siaka Dembele, C. Madhav Rao Vendra, and Jennifer Wen. "Numerical simulation of superheated jets using an Eulerian method." In ILASS2017 - 28th European Conference on Liquid Atomization and Spray Systems. Valencia: Universitat Politècnica València, 2017. http://dx.doi.org/10.4995/ilass2017.2017.4667.

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Flash boiling is the rapid phase change of a pressurised fluid that emerges in ambient conditions below its vapourpressure. Flashing can occur either inside or outside the nozzle depending on the local pressure and geometry and the bubble formation leads to interfacial interactions that eventually influence the emerging spray. Lagrangian methods which exist in literature to simulate the flash atomisation and inter-phase heat transfer employ many sim- plifying assumptions. Typically, sub-models used for the break-up, collisions and evaporation introduce an extensive empiricism that might result in unrealistic predictions for cases like flashing. In this study, a fully Eulerian approach is selected employing the Σ − Y model proposed by Vallet and Borghi. The model tracks liquid structures of any shape and computes the spray characteristics comprising a modified version for the transport equation of the sur- face density. The main goal of this study is to investigate the performance of this model in flash boiling liquids using the Homogeneous Relaxation Model (HRM) developed by Downar-Zapolski, a model capable of capturing the heat transfer under sudden depressurisation conditions accounting for the non-equilibrium vapour generation. The model in this present study considers that the instantaneous quality would relax to the equilibrium value over a given timescale which is calculated using the flow field values. A segregated approach linking the HRM and Σ − Y is implemented in a compressible formulation in an attempt to quantify the effects of flash boiling in the spray dynamics. The developed model is naturally implemented in RANS in a dedicated solver HRMSonicELSAFoam. Results from simulations of two-phase jets of different subcooled fluids through sharp-edged orifices show that the proposed approach can accurately simulate the primary atomisation and give reliable predictions for the droplet sizes and distribution. Strong effects of the flashing and turbulent mixing on the jet are demonstrated. The model istested for turbulent flows within small nozzles and was developed within the open source code OpenFOAM.DOI: http://dx.doi.org/10.4995/ILASS2017.2017.4667

Ban, Heng, and Zilong Hua. "Laser Flash Measurement of Samples With a Transparent Reference Layer." In ASME 2009 Heat Transfer Summer Conference collocated with the InterPACK09 and 3rd Energy Sustainability Conferences. ASMEDC, 2009. http://dx.doi.org/10.1115/ht2009-88584.

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The laser flash method is a standard method for thermal diffusivity measurement. This paper reports the development of a method and theory that extends the standard laser flash method to measure thermal conductivity and thermal diffusivity simultaneously. By attaching a transparent reference layer with known thermal properties on the back of a sample, the thermal conductivity and thermal diffusivity of the sample can be extracted from the temperature response of the interface between the sample and the reference layer to a heating pulse on the front surface. The theory can be applied for sample and reference layer with different thermal properties and thickness, and the original analysis of the laser flash method becomes a limiting case of the current theory with an infinitely small thickness of the reference layer. The uncertainty analysis was performed and results indicated that the laser flash method can be used to extract the thermal conductivity and diffusivity of the sample. The results can be applied to, for instance, opaque liquid in a quartz dish with silicon infrared detector measuring the temperature of liquid-quartz interface through the quartz.

Cheng, James C., and Jialiang Le. "Challenge Face by Truck Frontal Crash Analysis." In ASME 1994 International Computers in Engineering Conference and Exhibition and the ASME 1994 8th Annual Database Symposium collocated with the ASME 1994 Design Technical Conferences. American Society of Mechanical Engineers, 1994. http://dx.doi.org/10.1115/cie1994-0450.

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Abstract In the front barrier crash, due to basic structural differences, light truck body-on-frame vehicles behave quite differently man unitized body vehicles. The complexities of the vehicle structure, weight variation of the test condition, and inherent limited crash distance have made CAE analysis a very attractive method to reduce prototype testing and shorten the design cycle time. The deceleration of the vehicle experienced by the occupant, or “crash pulse”, plays a key role in evaluating occupant injury. In order to maximize CAE’s contribution to design, a reasonable prediction of the crash pulse is crucial. For body-on-frame vehicles, body mounts that connect the cab to the chassis have a pronounced effect on the crash pulse. However, the crash characteristic of the body mount is not fully understood. Therefore, a procedure was developed to provide a good estimation of their behavior. This procedure uses a spring-mass model and a finite element model to simulate a frontal barrier crash test. In both models, the body mounts were modeled as nonlinear springs. By correlating the vehicle response at different locations, a reasonable prediction of the body mounts can be obtained. Further design iterations can be performed once the body mounts characteristic is determined.

Lee, Bong-Sang, Sang-Yoon Park, and Min-Chul Kim. "Experimental Observation of Front-Face-Displacement and Load-Line-Displacement in CT and Bend Specimens During Fracture Toughness Tests." In ASME 2009 Pressure Vessels and Piping Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/pvp2009-77977.

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The master curve method described in ASTM E1921 provides a tool for using small specimens such as sub-sized CT and PCVN specimens for standard fracture toughness testing. However, a direct measurement of the load-line displacement of small specimens is not practical for standard fracture toughness tests. Mostly, the front-face displacement or the crack mouth opening displacement can be measured and converted into the load-line displacement by using an analytical relationship proposed by several investigators. Since those relationships were deduced from numerical calculations of the loaded specimens, experimental deviations may occur because of specimen indentation, rotation and arm bending during an actual testing. It is clear that the determination of fracture toughness is influenced by the accuracy of the estimation of load-line displacement as well as the load measurement. In this study, the relationship between the load-line displacement and the front-face displacement or the crack mouth displacement was investigated experimentally by using a series of CT and Bend specimens modified to measure the two displacements simultaneously during a single test. The results showed that the front-face measurement of CT specimens may result in about 3% more conservative estimate of fracture toughness. In the case of bend specimens, the crack mouth opening displacement measurement may result in about 7% non-conservative estimate of fracture toughness than the load-line measurement.

Oh, Tae Kyung, Danesh Tafti, and Krishnamurthy Nagendra. "LES-Conjugate Heat Transfer Analysis of a Ribbed Cooling Passage Using the Immersed Boundary Method." In ASME Turbo Expo 2019: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/gt2019-90397.

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Abstract The present study focuses on evaluating fully-coupled conjugate heat transfer simulation in a ribbed cooling passage with a fully developed flow assumption using LES with the immersed boundary method (IBM-LES-CHT). The IBM-LES and the IBM-CHT frameworks are validated prior to the main simulations by simulating purely convective heat transfer in the ribbed duct, and a laminar boundary layer flow over a 2D flat plate with heat conduction, respectively. For the main conjugate simulations, a ribbed duct geometry with a blockage ratio of 0.3 is simulated at a bulk Reynolds number of 10,000 with a conjugate boundary condition applied to the rib surface. The nominal Biot number is kept at 1, which is similar to the comparative experiment. As a means to overcome a large time scale disparity between the fluid and the solid regions, the use of a high artificial solid thermal diffusivity is compared to the physical diffusivity. It is shown that while the diffusivity impacts the instantaneous fluctuations in temperature, heat transfer and Nusselt numbers, it has an insignificantly small effect on the mean Nusselt number. Comparison between IBM-LES-CHT and iso-flux heat transfer simulations shows that the iso-flux case predicts higher local Nusselt numbers at the back face of the rib. Furthermore, the local Nusselt number augmentation ratio (EF) predicted by IBM-LES-CHT is compared to experiment and another LES conjugate simulation. Even though there is a mismatch between IBM-LES-CHT predictions and other two studies at the front face of the rib, the area-averaged EF compares reasonably well in other regions between IBM-LES-CHT prediction and the comparative studies.